Psy 201 Stats HW: 6
When constructing a scientific conclusion, you need to consider a. the statistical evidence b. the methodological rigor of the control procedures used to collect the data c. the results of other similar studies in the scientific literature d. All of these
All of these
The "point-and-whisker" plot displays the _______ for each condition (Choose all that apply). a. Mean b. Median c. 95% CI around the mean d. Standard deviation
a. Mean b. Median c. 95% CI around the mean
When summarizing statistical evidence, you need to include which of the following? (Choose all that apply) a. Means and SDs for each condition b. the obtained t value, df, p value and d c. if the observed mean difference was likely the result of sampling error.
a. Means and SDs for each condition b. the obtained t value, df, p value and d c. if the observed mean difference was likely the result of sampling error.
In this study your research team used solid procedural controls like counterbalancing the order of experimental conditions to reduce potential methodological flaws. Why is this important? a. Poor methodology can make interpreting statistical results impossible. b. If you don't use counterbalancing when collecting your data computer programs will not provide you with statistical results.
a. Poor methodology can make interpreting statistical results impossible.
The two effect sizes computed in this section (dz = 1.56 and gav = .51) were both computed from the same data but using different formulas. Why is it important to report which effect size formula you used? a. The two formulas often produce dramatically different effect size estimates with dramatically different interpretations b. The dSDd tends to produce smaller effect size estimates than the dSDp.
a. The two formulas often produce dramatically different effect size estimates with dramatically different interpretations
To compute the effect size, you divide the observed deviation between the means by a. a measure of the variability in the data. b. the SEM. c. the obtained t value.
a. a measure of the variability in the data.
As with all types of t tests (e.g., single sample t test and others), a t value that is close to zero suggests that the data are a. compatible with the null hypothesis. b. Incompatible with the null hypothesis.
a. compatible with the null hypothesis
The effect size (d = .60) suggests a. that the cognitive load generated by the Apple system was .60 of a standard deviation higher than that generated by the Google/Android system. b. the difference between the Apple and Google/Android system is probably not practically important c. The Apple system generates 60% more cognitive load that the Google/Android system
a. that the cognitive load generated by the Apple system was .60 of a standard deviation higher than that generated by the Google/Android system.
The effect size (dz= 1.56) suggests (choose all that apply) a. that the number of off-road glances generated by keyboard texting was 1.56 of a standard deviation higher than that generated by VTTT. b. the observed mean difference in off-road glances probably has practical importance.
a. that the number of off-road glances generated by keyboard texting was 1.56 of a standard deviation higher than that generated by VTTT. b. the observed mean difference in off-road glances probably has practical importance.
Figure 6.1 indicates that a. the keyboard texting group had more off-road glances than VTTT b. the VTTT group had more off-road glances than keyboard texting
a. the keyboard texting group had more off-road glances than VTTT
Researchers use the related samples t test to determine if ________ differ more than would be expected by sampling error. a. two related sample means b. a sample mean and a population mean
a. two related sample means
When composing a scientific conclusion you should address which of the following? (Choose all that apply) a. which condition did better b. if the difference was more than expected due to sampling error c. if the effect size had practical importance d. the methodological rigor of the study e. the previous research in the scientific literature
a. which condition did better b. if the difference was more than expected due to sampling error c. if the effect size had practical importance d. the methodological rigor of the study e. the previous research in the scientific literature
In this research situation which of the following results would be consistent with the scientific hypothesis? a. A higher mean in the VTTT condition and a small p value. b. A higher mean in the keyboard condition and a small p value. c. A higher mean in the VTTT condition and a large p value. d. A higher mean in the keyboard condition and a large p value.
b. A higher mean in the keyboard condition and a small p value.
Difference scores will always be positive. a. True b. False
b. False
The results of this study were similar to Strayer et al. (2017), why is that important? a. Your study in unimportant because other researchers already proved the similar conclusion with certainty. b. If your study's results are similar to those of previous researchers you can be more confident in the conclusion.
b. If your study's results are similar to those of previous researchers you can be more confident in the conclusion.
The research situation described here is using a a. Matched design. b. Repeated measures design
b. Repeated measures design.
You use a related samples t statistic when: (choose two) a. There are two independent samples and the outcome variable is measured on an interval/ratio scale b. There are two matched samples and the outcome variable is measured on an interval/ratio scale. c. There is one sample, the outcome variable is measured on an interval/ratio scale, and the outcome variable is measured twice from that same sample each time in a different condition. d. There is one sample and the outcome variable is measured on an interval/ratio scale and you do not know the population standard deviation. e. There is one sample and the outcome variable is measured on an interval/ratio scale and you do know the population standard deviation
b. There are two matched samples and the outcome variable is measured on an interval/ratio scale. d. There is one sample and the outcome variable is measured on an interval/ratio scale and you do not know the population standard deviation.
As with all types of t tests (e.g., single sample t test and others), a p value that is close to zero value suggests that the data are a. compatible with the null hypothesis. b. Incompatible with the null hypoth
b. incompatible with the null hypothesis
If the p value (i.e., in this case, p < .001) is small, the difference between the two means is a. likely to be due to sampling error. b. not likely to be due to sampling error
b. not likely to be due to sampling error
In general, the more the two confidence intervals overlap in a graph comparing two treatment conditions, the closer to ___________ the p value in the hypothesis test. a. zero b. one
b. one
uD is the symbolic notation for a. the null hypothesis. b. the mean of the difference scores if the null hypothesis is true.
b. the mean of the difference scores if the null hypothesis is true.
The denominators of the single sample t test and the related samples t test are both a. expected to be 0 if the null is true. b. the typical amount of sampling error expected in the study.
b. the typical amount of sampling error expected in the study.
Which of the following best represents the null hypothesis for a two-tailed related samples t test? a. uD =/ 0. b. uD = 0.
b. uD = 0
If the p value is p < .001 it means that there is less than a .001 probability of getting the obtained t value if a. The null hypothesis is true. b. There is no methodological flaw in the study. c. Both of the above.
c. Both of the above
Which of the following values is a measure of sampling error? a. SSD b. SDD c. SEMr
c. SEMr
The related samples t test can be used for a study that is using a. a matching approach. b. a pre-post approach. c. both approaches
c. both approaches
The p value from the related samples t test (p < .001) a. indicates that the VTTT's superior performance could not have occurred due to sampling error. b. proves that VTTT is superior to the Apple keyboard texting. c. is compelling evidence of the superiority of VTTT as long as the study had no methodological flaws
c. is compelling evidence of the superiority of VTTT as long as the study had no methodological flaws
The p value from the related samples t test (p = .015). a. indicates that the Google/Android system's superior performance could not have occurred due to sampling error. b. proves that the Google/Android system is superior to the Apple system. c. is compelling evidence of the superiority of the Google/Android system as long as the study had no methodological flaws, but it is still possible that the results occurred due to sampling error.
c. is compelling evidence of the superiority of the Google/Android system as long as the study had no methodological flaws, but it is still possible that the results occurred due to sampling error.
Which of the following common statistical assumptions is NOT an assumption of the related samples t test? a. Data independence b. Appropriate measurement of the variables c. The distribution of sample mean differences must have a normal d. Homogeneity of variance
d. Homogeneity of variance